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Pp. 34 and 785. Moulding Machines.óBy the use of the
hydraulic machine shewn in Fig. 902, which is made by Messrs.
Bopp & Reuther of Mannheim, the pressing of the sand is per-
formed simultaneously in both moulding boxes, and the removal
of the latter effected at one operation, thus accelerating the

The hydraulic cylinder G contains a ram F, which supports a
table u carrying the lower box E, and the constant pressure in
cylinders s s balances the dead weight. The pattern plate A, to
which are attached the two half-patterns B and c, is run into
position along the rails shown. The upper box D is supported
on a frame which can slide on vertical rods Q Q, and is connected
to the ram F by the piston rod H, the crosshead j, and the ropes
passing round the pulleys M N K L; so it follows that the raising
of E will lower D, and vice versd.

The pattern plate A being admitted, the boxes are filled with
sand, and a suitable presser block placed at T. The pressure
water is next let into the ram, and as E is raised to meet the
plate, D is simultaneously lowered, after which E, A, and D rise
together till they reach the block T; thus putting the required
compression on the sand. The valve R being now opened to
exhaust, the pressure is removed, and the ram again falls, lowering
the pieces E, A, and D : together at first. The moment, however,
that E detaches itself from plate A, so also does D begin to
rise; and when they all take the positions shewn, the boxes
may be removed and the operations repeated with a new pair of